1. Field of the Invention
This invention relates to a line powered voltage regulator for use where high input impedance and low-current drain are required such as in coin telephones.
2. Description of the Prior Art
Various voltage regulators are well known in the art including such regulators as Zener diodes, shunt and series regulators. These existing regulators have various limitations such as excessive quiescent current drain, inadequate temperature compensation, relative complexity, and low imput impedance which prevent their use in some applications. One such application is in a coin telephone where a relatively simple, line powered voltage regulator having high input impedance to a-c signals, low quiescent current drain and good regulation over a broad temperature range is needed.
Accordingly, it is an object of this invention to improve voltage regulators to provide good regulation over a broad temperature range.
Another object is to provide a voltage regulator for applications requiring relatively simple circuits, high input impedance, low quiescent current drain and good regulation over a broad temperature range.